Specifically, everything in http://mxr.mozilla.org/mozilla-central/source/dom/interfaces/events/nsIDOMNSEvent.idl except isTrusted really ought not to exist at all.
Bug 674696 Comment 0 Edit History
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Everything at https://searchfox.org/mozilla-central/source/dom/webidl/Event.webidl#64-88 really ought not to exist at all.